Doorknob locking device

ABSTRACT

A locking device serves to prevent the insertion of a key into a keyhole on a doorknob and for this purpose includes a hasp which straddles the narrowed neck of the doorknob and an outer guard supported by the hasp overlies the keyhole to prevent insertion of a key. A lock member, preferably of the tumbler type, closes the open end of the hasp to keep the guard over the keyhole and prevent its removal from the doorknob and is movable along the hasp to a selected position.

nited States Patent 1 Jones 1 DOORKNOB LOCKING DEVICE [76] Inventor: Ivan R. Jones, 1053 West Shepperd Avenue, Littleton, Colo. 80120 22 Filed: Apr. 21, 1971 21 App1.No.i 136,100

52 use]. 70/428, 70/53 511 mu E05b 17/14 [58] Field ofSearch ..'/0/ 3s A,53,416,

70/428, 431, 455, mo. 56, mo. 58

[56] References Cited UNITED STATES PATENTS 7/1969 Barber 70/424 8/1949 Bennett et a1. 70/38 A X June 12, 1973 2,911,814 11/1959 Williams 70/38 A X Primary ExaminerAlbert G. Craig, Jr. AttorneyReilly & Lewis [57] ABSTRACT A locking device serves to prevent the insertion of a key into a keyhole on a doorknob and for this purpose includes a hasp which straddles the narrowed neck of the doorknob and an outer guard supported by the hasp overlies the keyhole to prevent insertion of a key. A lock member, preferably of the tumbler type, closes the open end of the hasp to keep the guard over the keyhole and prevent its removal from the doorknob and is movable along the hasp to a selected position.

4 Claims, 5 Drawing Figures PAINTED I 2 I973 INVENTOR BY IVAN R. V2

ATTORNEYS DOORKNOB LOCKING DEVICE This invention relates to a novel and improved locking device and specifically of the type adapted to prevent insertion of a key into a doorknob.

There are a number of situations in which it is desirable to prevent access through a door equipped with the conventional key-actuated lock located in the outer face of a doorknob. Doorknob-mounted lock devices have heretofore been devised to bar access to a keyhole and to limiting turning or jimmying of the lock on the doorknob. For instance, such locking devices prevent turning of the knob by enclosing the knob and some clamp the knob against rotary movement, while othersblock insertion of the key into the keyhole but have required complicated locking or clamping mechanism and have not been dependable in use. In prior attempts to block key insertion into the doorknob, two separable knob-engaging components have been located at diametrically opposite positions on the doorknob but there are obvious drawbacks and difficulties attendant to the use of a two-piece construction.

The present invention is intended to afford definite advantages over the prior art in a novel and inexpensive locking device which can be releasably mounted on the doorknob and prevents insertion of the key into the conventional lock on the door, which is principally characterized by a one-piece doorknob locking unit device which can be easily fabricated and can be quickly and securely but releasably mounted on the doorknob in such a way as to be highly reliable in use.

Accordingly, it is an object of this invention to provide a novel and improved door-mounted locking de- .vice which can be easily fabricated and releasably locked onto the doorknob in a dependable and highly effective manner.

Another object of the present invention is to provide a novel doorknob locking device which is relatively simple and inexpensive to manufacture and is readily conformable to a variety of sizes and shapes of doorknobs.

Yet a further object of this invention is to provide a novel door locking device characterized by an integral one-piece doorknob encompassing unit having a hasp adapted to straddle the narrow neck of the doorknob and an outer guard supported by arms projecting outwardly from the hasp to surround the knob and a lock closing the hasp about the neck of the doorknob.

In accordance with the present invention in a preferred form shown there is provided a hasp arranged for straddling the narrowed neck of the doorknob having an outer guard assembly including a generally U- shaped bracket fixedly secured to the hasp to extend across the face of the knob and prevent insertion, the hasp and bracket being made of metal stock, preferably secured together by welding to form a one-piece lockencompassing unit. An adjustable tumbler-type lock with a pair of spaced apart open-ended sockets slides j over the ends of the hasp to close the open end of the hasp around the neck of the doorknob and the lock is selectively movable and positioned by locking same to the hasp to retain the bracket over the keyhole in the doorknob and may also prevent key insertion into a keyhole below the doorknob. The lock has keyactuated tumbler elements which associate with a set of aligned notches in the side legs of the hasp to secure the lock in place.

Other objects, advantages and capabilities of the present invention will become more apparent as the description proceeds taken in conjunction with the accompanying drawings in which:

FIG. 1 is a perspective view of a door lock device mounted in an operative position on a doorknob;

FIG. 2 is a front end elevational view of the door lock device shown in FIG. 1;

FIG. 3 is a bottom plan view thereof;

FIG. 4 is a side elevation view thereof; and

FIG. 5 is a top plan view thereof.

Referring now to the drawings, in FIG. I there is shown a portion of a conventional door assembly for the purpose of illustrating the features of the present invention, said door assembly including a doorknob 10 projecting outwardly from a vertical door-mounted plate 11. The conventional doorknob includes an outer knob 12 and a narrowed inner neck 13. A conventional door may have a keyhole 14 located below the doorknob in the plate 11 and/or in the front face of the doorknob (not shown). A door locking device 15 is shown in FIG. 1 in an operative position on the doorknob 10. The door locking device includes a generally U-shaped hasp 16 including a pair of spaced parallel side legs 16a and 16b and a curved upper end portion 16c joining the side legs which straddles the inner neck of the doorknob positioning the side legs in a depending relation on each side of the neck. Each of the side legs has a series of spaced notches 18 formed in the front side thereof with a notch on one side leg being aligned with a notch on the other side leg to provide a plurality of sets of aligned notches. Side leg 16a is of greater length than side leg 16b and is provided with a C-shaped stop 19 at the end thereof which allows the lock assembly hereinafter described to be rotated to one side for removal from the doorknob and the stop 19 prevents the lock from becoming separated from the hasp when the lock is in the unlocked position. The side legs are spaced so that the open end of the hasp will slide past the narrowed neck 13 but are sufficiently close together so that the side legs of the hasp cannot be slide outwardly over the enlarged knob 12.

An outer guard projects outwardly from the hasp to surround the doorknob and includes a generally U- shaped bracket having a pair of spaced side arms 21 and 22 which are secured at the ends of inner inturned end portions 23 to the sides of the hasp member, together with an intermediate closure portion 24 joining the outer ends of the side arms. The bracket is formed of a unitary rod preferably made of metal rod stock and the inner ends of the side arms are fixedly secured to the side legs as by welding approximately at the point where the upper ends of the side legs merge with the outer end portion. The securing of the bracket to the hasp forms a one-piece lock-encompassing unit which may be readily slid over the doorknob. The shape of the hasp and bracket will serve to align the closure portion over the keyhole in the-doorknob. As shown in FIG. 1, the side arms rest on the periphery of the knob. For smaller doorknobs the upper end portion may rest on the neck of the doorknob. A circular disc 25 is fixedly secured across the front of the bracket to form a part of the intermediate closure portion 24 and serves as a guard to cover a major portion of the front face of the doorknob to prevent any possibility of the insertion of a key thereinto.

A tumbler-type lock assembly generally designated 31 is shown as being slidably mounted on the side legs of the hasp and extends across these side legs to close off the open end of the U-shaped hasp to prevent its removal from the doorknob and keep the guard over the keyhole in the doorknob and at the same time, when positioned over the keyhole 14 in the door plate below the doorknob, serves to block insertion of the key into the keyhole 14. This tumble-type lock assembly 31 is of a conventional construction and includes a generally cylindrical housing 32 having a pair of spaced parallel openings 33 in the ends thereof through which the side legs of the hasp are inserted and in which the side legs slidably move. The housing contains a cylinder-type lock 34 into which a key 35 inserts. Within the lock there are tumbler segments 36 having edges alternately movable radially into and from the space inside at least one socket 33 to cooperate with one of the notches on the hasp and secure the tumbler-type lock assembly against further movement on the hasp and block insertion of a key into the keyhole below the doorknob.

In the use of the above-described locking device the door has previously been locked with the conventional key lock. The key 35 is moved to the released position and one end of the lock assembly is slid past the end of the shorter side leg 16b. The open end of the hasp is inserted down over the neck of the doorknob until the closure portion 24 of the bracket and disc 25 forming the guard are positioned over the key in the doorknob. The lock assembly is then slid back over side leg 16b and moved until it is in a position to block either the keyhole in the doorknob or the keyhole 14 in the door plate. The key 35 is turned to move the tumbler elements against an aligned set of the notches in the hasp and the key 35 is then removed from the lock assembly.

From the foregoing, it is apparent that the one-piece locking unit is readily conformable to a variety of sizes and shapes of doorknobs since the neck portions of most doorknobs are generally the same size and further the outer bracket forming the guard can be made relatively large with respect to the doorknob and still block the key insertion.

Although the present invention has been described with a certain degree of particularly, it is understood that the present disclosure has been made by way of example and that changes in details of structure may be made without departing from the spirit thereof.

What is claimed is:

l. A doorknob locking device adapted to mount on a doorknob unit having a front doorknob provided with a narrowed neck behind the doorknob comprising:

a one-piece doorknob locking unit adapted to slide over the doorknob, said unit including a generally U-shaped hasp having a pair of side legs and a closed end portion joining the side legs for straddling the neck of the doorknob, a bracket having opposite side arms rigidly attached to the side legs and extending normal thereto and forwardly around opposite sides of the doorknob and an intermediate closure portion joining the side legs and overlying the outer face of the doorknob to block the insertion of a key into the doorknob, and

adjustable lock means extending between said side legs to close the open end of the hasp around the neck portion of the knob, said lock means being adjustable lengthwise of the side legs and selectively movable into locking engagement with the side legs whereby to retain said closure portion over the outer face of the doorknob.

2. A doorknob locking device as set forth in claim 1 wherein one of said side legs is longer than the other and the longer side leg has a terminal stop preventing the lock member from sliding from the hasp.

3. A doorknob locking device as set forth in claim 1 wherein said lock member is of the tumbler type and actuated by a key in a cylinder, said cylinder being operatively associated with tumbler elements alternately movable into and out of engagement with a series of notches in the hasp.

4. A doorknob locking device adapted to mount on a doorknob unit of the type having a front doorknob and a narrowed neck portion behind the doorknob comprising:

a generally U-shaped hasp including a pair of said legs and a closed end portion for straddling the narrowed neck portion of the doorknob, each said side leg having a series of notches formed at spaced intervals along the length thereof,

an outer guard projecting forwardly from the hasp around the midsection of the doorknob when the hasp is straddling the neck portion, said guard including a bracket having a pair of side arms with intumed inner ends rigidly attached to the side legs of the hasp adjacent the closed end portion and an intermediate closure portion joined to the side arms extending normally of the side arms across the outer face of the doorknob and a disk affixed to the outer surface of the bracket and dimensioned to cover the outer face of the doorknob so as to block the insertion of a key into the doorknob, and tumbler-type lock member extending across said side legs, said lock having a pair of spaced parallel open-ended sockets through which said side legs slidably move, said lock having at least one keyactuated inner tumbler element alternately movable out into the socket to a selected notch in at least one of the hasp legs in a lock position and movable back into the socket in a retracted position whereby to position the lock member at a selected position along the side legs and block the insertion of a key into a keyhole on the doorknob.

* t I. k 

1. A doorknob locking device adapted to mount on a doorknob unit having a front doorknob provided with a narrowed neck behind the doorknob comprising: a one-piece doorknob locking unit adapted to slide over the doorknob, said unit including a generally U-shaped hasp having a pair of side legs and a closed end portion joining the side legs for straddling the neck of the doorknob, a bracket having opposite side arms rigidly attached to the side legs and extending normal thereto and forwardly around opposite sides of the doorknob and an intermediate closure portion joining the side legs and overlying the outer face of the doorknob to block the insertion of a key into the doorknob, and adjustable lock means extending between said side legs to close the open end of the hasp around the neck portion of the knob, said lock means being adjustable lengthwise of the side legs and selectively movable into locking engagement with the side legs whereby to retain said closure portion over the outer face of the doorknob.
 2. A doorknob locking device as set forth in claim 1 wherein one of said side legs is longer than the other and the longer side leg has a terminal stop preventing the lock member from sliding from the hasp.
 3. A doorknob locking device as set forth in claim 1 wherein said lock member is of the tumbler type and actuated by a key in a cylinder, said cylinder being operatively associated with tumbler elements alternately movable into and out of engagement with a series of notches in the hasp.
 4. A doorknob locking device adapted to mount on a doorknob unit of the type having a front doorknob and a narrowed neck portion behind the doorknob comprising: a generally U-shaped hasp including a pair of said legs and a closed End portion for straddling the narrowed neck portion of the doorknob, each said side leg having a series of notches formed at spaced intervals along the length thereof, an outer guard projecting forwardly from the hasp around the midsection of the doorknob when the hasp is straddling the neck portion, said guard including a bracket having a pair of side arms with inturned inner ends rigidly attached to the side legs of the hasp adjacent the closed end portion and an intermediate closure portion joined to the side arms extending normally of the side arms across the outer face of the doorknob and a disk affixed to the outer surface of the bracket and dimensioned to cover the outer face of the doorknob so as to block the insertion of a key into the doorknob, and a tumbler-type lock member extending across said side legs, said lock having a pair of spaced parallel open-ended sockets through which said side legs slidably move, said lock having at least one key-actuated inner tumbler element alternately movable out into the socket to a selected notch in at least one of the hasp legs in a lock position and movable back into the socket in a retracted position whereby to position the lock member at a selected position along the side legs and block the insertion of a key into a keyhole on the doorknob. 